[Bug java/83647] New: add x86_64 Windows support to GCJ

[Bug java/83647] New: add x86_64 Windows support to GCJ

[yzhang1985 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83647

            Bug ID: 83647
           Summary: add x86_64 Windows support to GCJ
           Product: gcc
           Version: 6.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: java
          Assignee: unassigned at gcc dot gnu.org
          Reporter: yzhang1985 at gmail dot com
  Target Milestone: ---

Created attachment 43002
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43002&action=edit
The changes to natVMConsole.cc are only for MingW. Probably these changes don't
need to be in GCC and can be downstream

GCJ currently doesn't support x86_64 Windows, specifically x86_64-w64-mingw32. 

I have made a patch that supports it. I know GCJ has been removed from GCC 7,
but I'm hoping this can still make it into GCC 6.


The changes were mostly to change 32bit ints to pointer sized ints.
Specifically,

unsigned long -> uintptr_t
jint -> jlong

Changing jint -> jlong is probably not right because that would change 32bit
builds. I wanted to change those jint to jsize and change jsize from int to
intptr_t, but wasn't sure of the effects.

The other big change was I had to replace boehm-gc with a newer version (7.2e,
7.2g crashes). GCC seems to have an out of date, custom version that doesn't
support x86_64 windows, and that only builds a static lib. I didn't include
that in the patch, but you can simply plant the newer version into the source
code.
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Subject: [Bug java/83647] add x86_64 Windows support to GCJ
Date: Mon, 01 Jan 2018 20:23:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83647

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |WONTFIX

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
GCC 6 is in regression only fixes due to it being a release branch.

Won't fix as Java was removed from GCC 7.  There are other open source Java
implementations including but not limited to OpenJDK.
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From: "yzhang1985 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug java/83647] add x86_64 Windows support to GCJ
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83647

--- Comment #2 from Yale Zhang <yzhang1985 at gmail dot com> ---
(In reply to Andrew Pinski from comment #1)
> GCC 6 is in regression only fixes due to it being a release branch.
> 
> Won't fix as Java was removed from GCC 7.  There are other open source Java
> implementations including but not limited to OpenJDK.

I was afraid of that, but I want to compile to native code and AFAIK, GCJ is
the only one or if not, the only robust one. I think this change can be useful
to others and shouldn't be lost just because GCC 6 is limited to regression
fixes only. Is there a non-release branch that this can checked into?
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Subject: [Bug java/45433] Can't find GCCMain in
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=45433

Bruno Haible <bruno at clisp dot org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bruno at clisp dot org

--- Comment #3 from Bruno Haible <bruno at clisp dot org> ---
(In reply to Jakub Jelinek from comment #2)
> You need to read the documentation, which would tell you you need to use
> -fmain=HelloWorld option.

It is true that -fmain=HelloWorld was missing in the reporter's command line.
But if that had been the only problem, the error message would have been

(.text+0x18): undefined reference to `main'

not

Exception in thread "main" java.lang.NoClassDefFoundError:
org.eclipse.jdt.internal.compiler.batch.GCCMain

The error message "java.lang.NoClassDefFoundError:
org.eclipse.jdt.internal.compiler.batch.GCCMain" means that the ecj1 program
cannot find the org.eclipse.jdt.internal.compiler.batch.GCCMain class, which it
expects to find in the jar file specified through the --with-ecj-jar option.

So, the reporter's real problem was that he configured GCC with a
--with-ecj-jar option without argument.
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Subject: [Bug java/45433] Can't find GCCMain in
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=45433

--- Comment #4 from Bruno Haible <bruno at clisp dot org> ---
I am having the same error, even with option -C (which does not need a
-fmain=... option):

$ gcj -v -C HelloWorld.java 
Using built-in specs.
COLLECT_GCC=/arch/x86-linux/gnu-inst-gcc/4.7.3/bin/gcj
Target: i686-pc-linux-gnu
Configured with: ../gcc-4.7.3/configure --build=i686-pc-linux-gnu
--host=i686-pc-linux-gnu --target=i686-pc-linux-gnu
--prefix=/arch/x86-linux/gnu-inst-gcc/4.7.3 --enable-shared
--enable-version-specific-runtime-libs --enable-nls --enable-threads=posix
--enable-__cxa_atexit --with-as=/arch/x86-linux/gnu/bin/as32
--with-gmp=/arch/x86-linux/gnu-inst-gcc/4.7.3
--with-mpfr=/arch/x86-linux/gnu-inst-gcc/4.7.3
--with-mpc=/arch/x86-linux/gnu-inst-gcc/4.7.3
--with-libelf=/arch/x86-linux/gnu-inst-gcc/4.7.3
--with-ecj-jar=/gfs/petix/Volumes/ExtData/source/gnu/gcc/sourceware.org-ecj/ecj-latest.jar
Thread model: posix
gcc version 4.7.3 (GCC) 
COLLECT_GCC_OPTIONS='-fsaw-java-file' '-B'
'/media/nas/pub/arch/x86-linux/gnu-inst-gcc/4.7.3/libexec/gcc/i686-pc-linux-gnu/4.7.3'
'-v' '-C'
'-fbootclasspath=./:/media/nas/pub/arch/x86-linux/gnu-inst-gcc/4.7.3/bin/../lib/gcc/../../share/java/libgcj-4.7.3.jar'
'-g1' '-fsyntax-only' '-femit-class-files' '-S' '-o' 'NONE' '-shared-libgcc'
'-mtune=generic' '-march=pentiumpro'

/media/nas/pub/arch/x86-linux/gnu-inst-gcc/4.7.3/libexec/gcc/i686-pc-linux-gnu/4.7.3/ecj1
HelloWorld.java -g1
-fbootclasspath=./:/media/nas/pub/arch/x86-linux/gnu-inst-gcc/4.7.3/bin/../lib/gcc/../../share/java/libgcj-4.7.3.jar
-g1 -fsource=1.5 -ftarget=1.5 -fzip-dependency /tmp/ccrzqP4M.zip
Exception in thread "main" java.lang.NoClassDefFoundError:
org.eclipse.jdt.internal.compiler.batch.GCCMain
   at gnu.java.lang.MainThread.run(MainThread.java:100)
Caused by: java.lang.ClassNotFoundException:
org.eclipse.jdt.internal.compiler.batch.GCCMain not found in
gnu.gcj.runtime.SystemClassLoader{urls=[],
parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}}
   at java.net.URLClassLoader.findClass(URLClassLoader.java)
   at gnu.gcj.runtime.SystemClassLoader.findClass(natSystemClassLoader.cc:27)
   at java.lang.ClassLoader.loadClass(ClassLoader.java)
   at java.lang.ClassLoader.loadClass(ClassLoader.java:387)
   at gnu.java.lang.MainThread.run(MainThread.java)

The problem is that the file that I specified as --with-ecj-jar value when
configuring GCC no longer exists. The GCC installation has not copied the file
to the GCC installation directory! But the ecj1 program still references it.

I cannot find an option to tell ecj1 about the new file name of ecj-latest.jar.
So I ended up creating a symlink so that the old file name still works.
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Subject: [Bug java/45433] Can't find GCCMain in
 org.eclipse.jdt.internal.compiler.batch.GCCMain
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=45433

Eric Gallager <egallager at gcc dot gnu.org> changed:

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----------------------------------------------------------------------------
                 CC|                            |egallager at gcc dot gnu.org

--- Comment #5 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to Bruno Haible from comment #4)
> I am having the same error, even with option -C (which does not need a
> -fmain=... option):
> 
> $ gcj -v -C HelloWorld.java 
> Using built-in specs.
> COLLECT_GCC=/arch/x86-linux/gnu-inst-gcc/4.7.3/bin/gcj
> Target: i686-pc-linux-gnu
> Configured with: ../gcc-4.7.3/configure --build=i686-pc-linux-gnu
> --host=i686-pc-linux-gnu --target=i686-pc-linux-gnu
> --prefix=/arch/x86-linux/gnu-inst-gcc/4.7.3 --enable-shared
> --enable-version-specific-runtime-libs --enable-nls --enable-threads=posix
> --enable-__cxa_atexit --with-as=/arch/x86-linux/gnu/bin/as32
> --with-gmp=/arch/x86-linux/gnu-inst-gcc/4.7.3
> --with-mpfr=/arch/x86-linux/gnu-inst-gcc/4.7.3
> --with-mpc=/arch/x86-linux/gnu-inst-gcc/4.7.3
> --with-libelf=/arch/x86-linux/gnu-inst-gcc/4.7.3
> --with-ecj-jar=/gfs/petix/Volumes/ExtData/source/gnu/gcc/sourceware.org-ecj/
> ecj-latest.jar
> Thread model: posix
> gcc version 4.7.3 (GCC) 
> COLLECT_GCC_OPTIONS='-fsaw-java-file' '-B'
> '/media/nas/pub/arch/x86-linux/gnu-inst-gcc/4.7.3/libexec/gcc/i686-pc-linux-
> gnu/4.7.3' '-v' '-C'
> '-fbootclasspath=./:/media/nas/pub/arch/x86-linux/gnu-inst-gcc/4.7.3/bin/../
> lib/gcc/../../share/java/libgcj-4.7.3.jar' '-g1' '-fsyntax-only'
> '-femit-class-files' '-S' '-o' 'NONE' '-shared-libgcc' '-mtune=generic'
> '-march=pentiumpro'
>  /media/nas/pub/arch/x86-linux/gnu-inst-gcc/4.7.3/libexec/gcc/i686-pc-linux-
> gnu/4.7.3/ecj1 HelloWorld.java -g1
> -fbootclasspath=./:/media/nas/pub/arch/x86-linux/gnu-inst-gcc/4.7.3/bin/../
> lib/gcc/../../share/java/libgcj-4.7.3.jar -g1 -fsource=1.5 -ftarget=1.5
> -fzip-dependency /tmp/ccrzqP4M.zip
> Exception in thread "main" java.lang.NoClassDefFoundError:
> org.eclipse.jdt.internal.compiler.batch.GCCMain
>    at gnu.java.lang.MainThread.run(MainThread.java:100)
> Caused by: java.lang.ClassNotFoundException:
> org.eclipse.jdt.internal.compiler.batch.GCCMain not found in
> gnu.gcj.runtime.SystemClassLoader{urls=[],
> parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}}
>    at java.net.URLClassLoader.findClass(URLClassLoader.java)
>    at gnu.gcj.runtime.SystemClassLoader.findClass(natSystemClassLoader.cc:27)
>    at java.lang.ClassLoader.loadClass(ClassLoader.java)
>    at java.lang.ClassLoader.loadClass(ClassLoader.java:387)
>    at gnu.java.lang.MainThread.run(MainThread.java)
> 
> The problem is that the file that I specified as --with-ecj-jar value when
> configuring GCC no longer exists. The GCC installation has not copied the
> file to the GCC installation directory! But the ecj1 program still
> references it.
> 
> I cannot find an option to tell ecj1 about the new file name of
> ecj-latest.jar. So I ended up creating a symlink so that the old file name
> still works.

GCC 4.7 is no longer supported; the only open branch where java is still
included is GCC 6, and it is only open for regression fixes and docs only.